WO 99/56883 shows (in FIG. 5) and describes an apparatus of this kind, in which the gas cleaning device includes first a number of conical separation discs rotatable with the centrifugal rotor and second a number of stationary conical separation discs. The stationary separation discs are arranged between the rotatable separation discs. The gas cleaning device further comprises a housing rotatable with said centrifugal rotor, said housing being provided with a gas inlet for the gas to be cleaned and supporting on its inside the rotatable separation discs, and a stationary central tube forming a gas outlet for cleaned gas and supporting on its outside the aforementioned stationary separation discs. A gas cleaning device designed in this way is relatively expensive to manufacture and, moreover, it requires a certain overpressure of the gas to be cleaned, to enable the gas to flow through the gas cleaning device.
WO 99/56883 also shows (in FIG. 7) an alternative embodiment of a gas cleaning device having conical separation discs. Also this gas cleaning device is relatively expensive to manufacture. Furthermore, a separate gas supply device is required, since the housing surrounding the centrifugal rotor for the cleaning of liquid, in this case, does not delimit any gas supply passage leading to the gas cleaning device.
The object of the present invention is to provide an apparatus for simultaneous cleaning of both a liquid and a gas, said apparatus being compact and relatively inexpensive to manufacture and, moreover, enabling cleaning of gas without the gas being subjected to a pressure drop on its passage through the gas cleaning device.